Method of making and using surface priming composition for proteinaceous substrates

ABSTRACT

An invented composition for promoting the adhesion of adhesives, coatings and/or composites to proteinaceous substrates is disclosed comprising a water-miscible solvent; and an unsaturated carboxylic acid of the general formula: ##STR1## where R 1  is selected from CH═CH, C(CH 3 )═C(CH 3 ), C(CH 3 )═CH, CH 2  CH 2 , or CH 2  CH 2  CH 2  ; and R 2  is selected from a terminally mono-, di-, tri-, or multi-unsaturated group. Methods of making the compound and methods of its use are also disclosed.

This is a divisional of application Ser. No. 130,603, filed Dec. 9,1987, now U.S. Pat. No. 4,863,993.

FIELD OF THE INVENTION

This invention relates to materials and methods for improving theadhesion of adhesives, coatings and composites to biological substrates,particularly proteinaceous surfaces, and more specifically to materialsand methods for improving the adhesion of free radical polymerizableadhesives, coatings and composites to proteinaceous substrates in vivo.Even more specifically, materials and methods for increasing the bondstrength of adhesives, coatings and composites to proteinaceoussubstrates for the purpose of restoration and adornment thereof withcosmetic prostheses are herein described.

DESCRIPTION OF THE PRIOR ART

The reparation, adornment, and prosthetic extension of keratinaceousstructures, namely, human fingernails and toe nails and livestock hoofs,has been a common practice for centuries. Fingernails are currentlyknown to be coated with multicolored nitrocellulose lacquers, repairedwith cyanoacryalate adhesives, and extended with the use of acrylicmonomer and polymer slurries or doughs that cure by peroxide/amine freeradical mechanisms. Although the nitrocellulose lacquers and thecyanoacrylate adhesives are relatively adherent to a fingernail plate,the acrylic materials employed for the purpose of creating an artificialfingernail prosthesis are not. Only after treatment of the fingernailsurface with an unsaturated carboxylic acid, such as methacrylic acid(current commercial embodiments containing in excess of 70 percentmethacrylic acid), will such acrylic monomer and polymer slurries ordoughs adhere to the nail plate. Such harsh treatment on a relativelyfragile surface poses a serious toxicological hazard due to thecorrosive nature of the unsaturated carboxylic acids. Other unsaturatedcarboxylic acids presently being used in the described applicationsinclude either alone or in part, acrylic acid and beta-carboxyethylacrylate. Lower concentrations of these unsaturated acids pose adecreased danger to the intact fingernail surface; however, at suchlower concentration the adhesion of the acrylic monomer and polymerslurry is minimized or lost completely. An analogous situation existswhen attempting to repair a split or fractured hoof in that without theapplication of the corrosive and possibly toxic levels of unsaturatedacids, very poor adhesion results.

Currently, the only known and readily practiced method for obtainingadhesion of prosthetic materials to wholly proteinaceous substrates,such as fingernails and hooves, has been the physical abrasion androughening of the proteinaceous substrate surface with a file,sand-paper-like, or other abrasive material, followed by the applicationof unsaturated carboxylic acid solutions (known in the artificialfingernail art as primers), followed lastly by the application of theprosthetic material. The prosthetic material is not inherently adhesiveto proteinaceous substrates. Rather, the prosthetic material alsocontains unsaturated groups, which, when curing, chemically react withthe unsaturated groups of the carboxylic acid solution applied to theproteinaceous substrate. Thus, an adhesive bond between said substrateand the prosthesis is provided.

The disadvantages of such a method and materials used in the prior artare as follows:

(1) too much physical abrasion or roughening of the proteinaceoussubstrate, particularly a living fingernail, can be harmful to thesubstrate;

(2) in the area of hoof binding, cracks and fissures in the hooves arenot readily abraded or roughened due to the inaccessibility of thesurface to such abrasive materials and methods;

(3) the unsaturated carboxylic acids that are often used (acrylic acidand methacrylic acid, either alone at full concentration of incombination with other diluents, are highly corrosive and can severelydamage the protein of a fingernail or hoof or the underlying orsurrounding living tissue; and

(4) even with such harsh surface preparation as described above, theadhesive bonds obtained with such methods are poor and all too ofteninadequate to retain the prosthetsis for sufficient periods of time orunder stress, thus causing the prosthetsis to break off in whole or inpart.

A number of patents showing various prior art adhesive compositions andfingernail treatments have been noted, including U.S. Pat. Nos.4,547,363, 4,209,604, 4,413,108, 4,521,550 and German Pat. No. DT2,557,536.

U.S. Pat. No. 4,547,363 discloses a fingernail strengthener depositedfrom solution onto the fingernail surface. These compositions are of noutility in achieving high bond strengths between proteinaceoussubstrates (such as fingernails) and free-radically polymerizedadhesives, coatings or composites.

U.S. Pat. No. 4,521,550 discloses materials and methods for obtaininghigh bond strengths to dentin, which is a partially proteinaceoussubstrate. The adhesion promoters of that invention are limited to theaddition reaction product of pyromellitic acid dianhydride and2-hydroxyethyl methacrylate (PMDM), the addition reaction product of3,3', 4,4'-benzophenonetetracarboxylic dianhydride and 2-hydroxyethylmethacrylate (BTDA-HEMA) and 4-methacryloxyethyltrimellitic anhydride(4-META). PMDM is shown herein to be inferior to the compositions of thepresent invention for achieving high bond strength to proteinaceoussubstrates.

The remaining patents noted above disclose a number of unsaturatedcarboxylic acid compounds to be included in anaerobic adhesivecompositions. These compositions are solvent-free. Most important,however, is that they are of no utility in covering, protecting oradorning surfaces, such as fingernails and livestock hooves, which areexposed to air (aerobic surfaces).

SUMMARY OF THE INVENTION

The present invention comprises materials and methods whichsubstantially increase the adhesive bond strength between adhesives,coatings or composites, and proteinaceous biological substrates such asfingernails and livestock hooves. The purpose of this invention is toprovide materials and methods for improved adhesive bonding of bothcomposite and unfilled coating and adhesive resins capable of freeradical-type polymerization to biological substrates composed wholly orin part of protein.

Briefly, the method of this invention is preferably accomplished bytreating the substrate to be adhered to with a non-aqueous solution ofan addition reaction product between a cyclic anhydride and a terminallyunsaturated molecule containing at least one hydroxyl group. An exampleof such a compound is the addition reaction product of maleic anhydrideand 2-hydroxyethyl methacrylate. The solution carrier is preferably anon-aqueous solvent capable of (1) dissolving the said addition reactionproduct(s) described above without precipitation or polymerizationduring storage and (2) forming a mixture, preferably azeotropic, withwater.

A most preferred embodiment of the invention utilizes the additionreaction product of maleic anhydride and 2-hydroxyethyl methacrylate ina carrier solvent of ethyl acetate. This solution is brushed, sprayed orotherwise applied to the substrate to be bonded and the ethyl acetate isallowed to completely evaporate. An adhesive, coating or composite isthen applied to the treated substrate and subsequently polymerized by afree radical mechanism. The polymerized adhesive, coating or compositewill be seen to adhere tenaciously to the pretreated substrate,achieving bond strengths unexpectedly high compared to pretreatment withother carboxyl-containing unsaturated adhesion promoters such asmethacrylic acid (CH₂ ═C(CH₃)COOH). The adhesion promoting additionreaction products of the present invention can be described in generalas: ##STR2## wherein R₁ is selected from CH═CH, C(CH₃)═C(CH₃),C(CH₃)═CH, CH₂ CH₂, and CH₂ CH₂ CH₂ ;

and R₂ is selected from a terminally mono-, di-, tri-, ormultifunctional unsaturated group.

As mentioned previously, these compounds are addition reaction productsbetween a cyclic anhydride and a hydroxyl-containing terminallyunsaturated molecule. Examples of cyclic anhydride precursors suitablefor obtaining these addition reaction products are maleic anhydride,dimethylmaleic anhydride, succinic anhydride, glutaric anhydride, andcitraconic anhydride. Any cyclic anhydride capable or ring openingduring the addition reaction is contemplated. Examples ofhydroxyl-containing terminally unsaturated molecules suitable forachieving the addition reaction products of this invention are2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate,2-hydroxybutyl (meth)acrylate, allyl alcohol, pentaerythritoltri(meth)acrylate, N-2-hydroxyethyl (meth)acrylamide and methallylalcohol. Any compound containing at least one hydroxyl group and atleast one terminal unsaturated group (acrylate, methacrylate, vinyl,acrylamide, methacrylamide, etc.) is contemplated to have utility in themanufacture of the addition reaction products of the present invention.

Examples of the addition reaction products of this invention are(meth)acryloyloxyethyl maleate, (meth)acryloyloxypropyl maleate,(meth)acryloyloxybutyl maleate, (meth)acryloyloxyethyl citraconate,(meth)acryloyloxypropyl citraconate, (meth)acryloyloxybutyl citraconate,(meth)acryloyloxyethyl dimethylmaleate, (meth)acryloyloxypropyldimethylmaleate, (meth)acryloyloxybutyl dimethylmaleate,(meth)acryloyloxyethyl succinate, (meth)acryloyloxyethyl glutarate,(meth)allyloyloxyethyl maleate and others.

A variety of solvents and solvent mixtures are useful for the practiceof this invention. These solvents are desirably volatile andwater-miscible, as well as being good solvents for the adhesionpromoters described above. More desirably they are capable of formingazeotropic mixtures with water, specifically for displacing adsorbedmoisture at the adhesion promoter/substrate interface. This adsorbedmoisture is undesirable when attempting to achieve high bond strengthsand decreases adhesion of adhesives, coatings and composites to avariety of substrates. An example of this decreased adhesion is observedon glass, which has a tendency to adsorb a layer of water, especiallyunder high humidity conditions. Thus displacement of adsorbed moistureis advantageous in achieving a high degree of adhesion. Suitablesolvents include, but are not limited to, acetone, ethyl acetate,isopropyl alcohol, ethanol, butyl acetate, n-propyl acetate, isopropylacetate, cyclohexane, n-hexane, isobutyl acetate, sec-butyl acetate,amyl acetate, isoamyl acetate, butanol, acetonitrile, N- methylpyrollidone, tetrahydrofuran, butyrolactone, and mixtures thereof. Informulating the adhesion promoting solutions of this invention that areintended for contact in vivo, attention should be paid to the use ofsolvents that are not harmful or dangerous to living tissue or pose asignificant environmental or work place hazard. The most preferredsolvents are ethyl acetate, isopropanol, ethanol and mixtures thereof.All three of these solvents are capable of forming azeotropic mixtureswith water, are relatively innocuous with respect to their interactionwith living tissue, dissolve the adhesion promoting agents of thisinvention, and are sufficiently volatile to evaporate completely in areasonable amount of time.

After priming the surface of a proteinaceous substrate with acomposition of the type disclosed herein, the surface may then becontacted with an adhesive, coating of composite providing greateradherence of such materials to the primed substrate, than to an unprimedsubstrate.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In general, this invention comprises materials and methods for improvingthe adhesive strength of adhesives, coatings and composites tobiological substrates. The terms "adhesives, coatings and composites"are taken to mean any composition that can be stored in either a singleor multi-component form, is used to adhere, cover, adorn, replace, orotherwise protect a surface, and can be polymerized by one or more of avariety of free radical-type initiation processes. Examples of suchmaterials are

(1) two-component (powder and liquid) artificial fingernail prosthesisformulations, which polymerize through a peroxide/tertiary amine typeinitiation;

(2) one component, glass/resin dental compositions, which arepolymerized by actinic (visible and/or ultraviolet) light activation ofa photoinitiator, together with an optional tertiary amine; and

(3) ultraviolet and visible light cured, unfilled or filled, coatingsand adhesives used to attach and/or cover natural or artificialfingernails; similar compositions are utilized for the reparation oflivestock hooves that have become split or cracked.

Although not limited to the above types of adhesives, coatings andcomposites, the three categories listed are those compositions that showmarked improvement in adhesive strength through the practice of thepresent invention.

The most preferred inventive method for pretreating the surfaces to beadhered to comprises contacting the surface with a non-aqueous solutionof a metacryloyloxyethyl maleate (herein referred to as MAHEMA), andallowing the non/aqueous solvent to completely evaporate. Then, theadhesive, coating or composite is allowed to contact the treated surfaceand polymerized through free radical mechanisms. The preferredconcentration of MAHEMA in the non-aqueous solvent is from about onepercent to about 30 percent, and the most preferred concentration isabout 5 to 20 percent. Differences in the porosity and surface freeenergy of the substrate will have a bearing on the optimal MAHEMAconcentration for each individual surface to be "primed". In general,following the complete evaporation of the carrier solvent, the treatedsubstrate should appear relatively dry. Treated surfaces that appearshiny and wet tend to have a thick layer of residual MAHEMA, which canact as a boundary layer and lead to decreased adhesive strength.

SYNTHESIS OF MAHEMA

MAHEMA was prepared by heating together 1 mole of maleic anhydride andslight excess of 1 mole of 2-hydroxyethyl methacrylate together withabout 200 ppm of the monomethyl ether of hydroquinone as a stabilizeragainst premature polymerization. In addition 500 ppm of triethylaminewas included in the reaction mixture as a catalyst for the additionreaction. Upon cooling, a slightly yellow, moderately viscous liquid isobtained, having a refractive index of 1.484 (at 20 degrees C.) and aBrookfield viscosity (at 23 degrees C.) of 470 cps. This liquid wasstored in amber glass bottles until further use. The structure of MAHEMAis as follows: ##STR3##

Care must be taken during the heating process above to keep the reactionprocess at or below about 80-90 degrees C. to avoid prematurepolymerization due to the mathacrylate group.

Alternatively, MAHEMA may be synthesized in the solvent carrier to beused in the practice of this invention. For example, the properlycalculated amounts of maleic anhydride and 2-hydroxyethyl methacrylatemay be added to ethyl acetate to provide the desired final concentrationof MAHEMA in situ. Attention must be paid to this method of synthesizingMAHEMA, in that certain solvents, such as isopropyl alcohol, can competewith the 2-hydroxyethyl methacrylate for addition to the anhydride groupof maleic anhydride.

ADHESIVE STRENGTH OF ADHESIVES, COATINGS AND COMPOSITES ON PROTEINACEOUSSUBSTRATES

Proteinaceous substrates were tested to demonstrate the adhesivestrength improvement caused by the adhesion promoting compositions ofthis invention. The differences in the adhesive strength provided bypretreating the substrate with the present invention relative to priorart systems are shown.

EXAMPLE 1

Solutions ranging from one to 30 percent MAHEMA in anhydrous ethylacetate were prepared and packaged in amber glass bottles with apolyethylene brush cap for application to the surfaces to be tested. Inorder to test the extent of adhesion improvement by the MAHEMA solutionson keratinaceous substrates, cattle hooves were chosen due to theiravailability and ease of handling during tensile adhesive strengthtesting. Flat sections of cattle hooves were prepared with the hooffibers running parallel to the surface to be tested. The hoof surfacewas then abraded with a fine grit sandpaper and subsequently rinsed withwater and allowed to dry thoroughly. The abraded and rinsed hoof surfacewas then treated with the MAHEMA solution, being brushed on and allowingthe ethyl acetate to evaporate completely. The surface of the hoof atthis point appeared dry and slightly glossy. A stainless steel cylinderwith a tapered bore and an access port was then contacted to the treatedhoof surface perpendicularly.

The following formulation was mixed, poured into the testing cylinderthrough the access port, and allowed to polymerize. This assembly wasallowed to age at room temperature for 24 hours and subsequently testedfor tensile adhesive strength in an Instron Tensile Strength TesterModel 1011 (Instron Corp, Quincy, Ma) at a crosshead speed of 0.1mm/minute.

    ______________________________________                                        Liquid A                                                                      Ethyl methacrylate       93%                                                  Ethylene glycol dimethacrylate                                                                         6%                                                   Dimethyl-p-toluidine     1%                                                   Powder B                                                                      Poly(ethyl-co-methyl methacrylate) polymer                                                             98.1%                                                Benzoyl peroxide         1.9%                                                 ______________________________________                                        Ratio of Liquid A:Powder B is approximately 1:3 in the                        final mixture.                                                                ______________________________________                                    

The following results were obtained.

    ______________________________________                                                                         No.                                          MAHEMA %  Avg. Adh.* Adh. Range**                                                                              Measurements                                 ______________________________________                                        0         240        110-330     5                                            1         570        400-670     5                                            2         720        460-790     5                                            3         780        600-840     5                                            4         800        690-880     5                                            5         870        810-910     5                                            8         080         940-1170   5                                             10        1410      1250-1500   5                                             13        1840      1610-1990   5                                             16        2320      1980-2500   5                                             20        2450      2020-2610   5                                             25        2030      1880-2150   5                                             30        1490      1200-1780   5                                            ______________________________________                                         *Average adhesion in psi (lbs per sq. inch)                                   **Adhesion range in psi (lbs per sq. inch)                               

EXAMPLE 2

The adhesion promoting capabilities of the maleic anhydride additionreaction products of this invention were compared to those of otherknown and/or potential adhesion promoters. All compounds tested had atleast one carboxylic group and at least one unsaturated group capable ofparticipating in free radical type polymerizations. Each promoter islisted below, together with its concentration, solvent (if any),substrate appearance, and tensile adhesive strength as described inExample 1.

    ______________________________________                                        Adhesion Promoter                                                                          Conc.    Solvent     Avg. Adh.sup.3                              ______________________________________                                        Methacrylic acid                                                                           20%      Ethyl acetate                                                                              680                                        Methacrylic acid                                                                           100%     None        1250                                        Acrylic acid 20%      Ethyl acetate                                                                              820                                        Acrylic acid 100%     None        1500                                        MAHEMA.sup.4 20%      Ethyl acetate                                                                             2510                                        PMDM.sup.1    5%      Acetone     1110                                        PMDM.sup.1   20%      Acetone      730                                        Maleic acid  20%      Ethyl acetate                                                                              300                                        MAHPMA.sup.2,4                                                                             20%      Ethyl acetate                                                                             2480                                        ______________________________________                                         .sup.1 Pyromellitic dianhydride/2hydroxyethyl methacrylate adduct (ref.       Patent No. 4,521,550)                                                         .sup.2 Maleic anhydride/2hydroxypropyl methacrylate adduct                    .sup.3 average adhesion in psi (lbs per sq. inch)                             .sup.4 Invented Compositions                                             

It is anticipated that just about any substrate comprised entirely or inpart of protein will be adhered to better by pretreatment of thesubstrate surface with the compositions of this invention. The precedingdisclosure has demonstrated the improved adhesion of a free-radicalinitiated composition to keratin substrates treated with MAHEMA andother cyclic anhydride addition reaction products as previouslydescribed. It is believed that substrates such as fingernails, hooves,bone, ivory, leather, dentin, enamel, and other partially or whollyproteinaceous materials will show the adhesion-promoted benefits of thepresent inventive compositions.

What I claim is:
 1. A method of making a composition for promoting theadhesion of adhesives, coatings and/or composites to proteinaceoussubstrates comprising the steps of:(a) providing a cyclic anhydride; (b)providing a hydroxyl-containing, terminally unsaturated reactant; (c)reacting said cyclic anhydride with said hydroxyl containing terminallyunsaturated reactant to form an unsaturated carboxylic acid of thegeneral formula: ##STR4## where R₁ is selected from CH═CH,C(CH₃)═C(CH₃), C(CH₃)═CH, CH₂ CH₂, or CH₂ CH₂ CH₂ ; andR₂ is selectedfrom a terminally mono-, di-, tri-, or multi-unsaturated group; (d)dissolving said adduct of step c in a water-miscible solvent.
 2. Themethod of claim 1 wherein said cyclic anhydride is selected from maleicanhydride, dimethylmaleic anhydride, succinic anhydride, glutaricanhydride and citraconic anydride.
 3. The method of claim 1 wherein saidhydroxyl containing terminally unsaturated reactant is selected from2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate,2-hydroxybutyl (meth)acrylate, allyl alcohol, pentaerythritoltri(meth)acrylate, N-2-hydroxyethyl (meth)acrylamide and methallylalcohol.
 4. The method of claim 1 wherein the cyclic anhydride is maleicanhydride and the hydroxyl containing terminally unsaturated reactants2-hydroxyethyl methacrylate.
 5. The method of claim 1 wherein saidwater-miscible solvent is selected from acetone, ethyl acetate,isopropyl alcohol, ethanol, butyl acetate, n-propyl acetate, isopropylacetate, cyclohexane, n-hexane, isobutyl acetate, sec-butyl acetate,amyl acetate, isoamyl acetate, butanol, acetonitrile, N-methylpyrollidone, tetrahydrofuran, butyrolactone, and mixtures thereof. 6.The method of claim 5 wherein said solvent is ethyl acetate.
 7. A methodof treating proteinaceous substrate to improve adhesion theretocomprising applying to said substrate the composition comprising:(a) awater-miscible solvent; and (b) an unsaturated carboxylic acid of thegeneral formula: ##STR5## where R₁ is selected from CH═CH,C(CH₃)═C(CH₃), C(CH₃)═CH, CH₂ CH₂, or CH₂ CH₂ CH₂ ; andR₂ is selectedfrom a terminally mono-, di-, tri-, or multi-unsaturated group; andallowing said composition to dry on said substrate.
 8. The compositionset forth in claim 7 wherein said adduct is selected from(meth)acryloyloxyethyl maleate, (meth)acryloyloxypropyl maleate,(meth)acryloyloxybutyl maleate, (meth)acryloyloxyethyl citraconate,(meth)acryloyloxypropyl citraconate, (meth)acryloyloxybutyl citraconate,(meth)acryloyloxyethyl dimethylmaleate, (meth)acryloyloxypropyldimethylmaleate, (meth)acryloyloxybutyl dimethylmaleate,(meth)acryloyloxyethyl succinate, (meth)acryloyloxyethyl glutarate and(meth)allyloyloxyethyl maleate.
 9. The composition set forth in claim 8wherein said adduct is methacryloyloxyethyl maleate.
 10. The compositionset forth in claim 7 wherein said water-miscible solvent is selectedfrom partially and wholly water-miscible solvents.
 11. The compositionset forth in claim 7 wherein said water-miscible solvent is selectedfrom acetone, ethyl acetate, isopropyl alcohol, ethanol, butyl acetate,n-propyl acetate, isopropyl acetate, cyclohexane, n-hexane, isobutylacetate, sec-butyl acetate, amyl acetate, isoamyl acetate, butanol,acetonitrile, N-methyl pyrollidone, tetrahydrofuran, butyrolactone, andmixtures thereof.
 12. The composition as set forth in claim 11 where thewater-miscible solvent is ethyl acetate.
 13. The composition of claim 7wherein said adduct is selected from (meth)acryloyloxyethyl maleate,(meth)acryloyloxypropyl maleate, (meth)acryloyloxybutyl maleate,(meth)acryloyloxyethyl citraconate, (meth)acryloyloxypropyl citraconate,(meth)acryloyloxybutyl citraconate, (meth)acryloyloxyethyldimethylmaleate, (meth)acryloyloxypropyl dimethylmaleate,(meth)acryloyloxybutyl dimethylmaleate, (meth)acryloyloxyethylsuccinate, (meth)acryloyloxyethyl glutarate and (meth)allyloyloxyethylmaleate.
 14. The composition of claim 7 wherein said compositioncomprises 1 to 30% by weight metacryloyloxyethyl maleate.
 15. Thecomposition of claim 7 comprising 5-20% by weight methacryloyloxyethylmaleate.
 16. The composition of claim 7 comprising 10% by weightmethacryloyloxyethyl maleate.
 17. A method of treating proteinaceoussubstrate to improve adhesion thereto comprising applying to saidsubstrate the composition comprising:(a) a water-miscible solvent; and(b)an unsaturated carboxylic acid of the general formula: ##STR6## andallowing said composition to dry on said substrate.
 18. The compositionset forth in claim 17 wherein said water-miscible solvent is selectedfrom acetone, ethyl acetate, isopropyl alcohol, ethanol, butyl acetate,n-propyl acetate, isopropyl acetate, cyclohexane, n-hexane, isobutylacetate, sec-butyl acetate, amyl acetate, isoamyl acetate, butanol,acetonitrile, N-methyl pyrollidone, tetrahydrofuran, butyrolactone, andmixtures thereof.
 19. The composition as set forth in claim 18 whereinthe water-miscible solvent is ethyl acetate.
 20. The composition as setforth in claim 19 wherein said composition comprises 1 to 30% by weightmethacryloyloxyethyl maleate.
 21. The composition as set forth in claim20 wherein said composition comprises 5 to 20% by weightmethacryloyloxyethyl maleate.
 22. The composition as set forth in claim21 wherein said composition comprises 10% by weight methacryloyloxyethylmaleate.
 23. A method of treating proteinaceous substrate to improveadhesion thereto comprising: applying to said substrate the compositioncomprising:(a) ethyl acetate; and (b) 10% by weight methacryloyloxyethylmaleate; and allowing said composition to dry on said substrate.